1 // SPDX-License-Identifier: GPL-2.0-only
3 * efi.c - EFI subsystem
5 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
6 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
7 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
9 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
10 * allowing the efivarfs to be mounted or the efivars module to be loaded.
11 * The existance of /sys/firmware/efi may also be used by userspace to
12 * determine that the system supports EFI.
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 #include <linux/kobject.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/debugfs.h>
21 #include <linux/device.h>
22 #include <linux/efi.h>
24 #include <linux/initrd.h>
26 #include <linux/kexec.h>
27 #include <linux/platform_device.h>
28 #include <linux/random.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/acpi.h>
32 #include <linux/ucs2_string.h>
33 #include <linux/memblock.h>
34 #include <linux/security.h>
36 #include <asm/early_ioremap.h>
38 struct efi __read_mostly efi
= {
39 .runtime_supported_mask
= EFI_RT_SUPPORTED_ALL
,
40 .acpi
= EFI_INVALID_TABLE_ADDR
,
41 .acpi20
= EFI_INVALID_TABLE_ADDR
,
42 .smbios
= EFI_INVALID_TABLE_ADDR
,
43 .smbios3
= EFI_INVALID_TABLE_ADDR
,
44 .esrt
= EFI_INVALID_TABLE_ADDR
,
45 .tpm_log
= EFI_INVALID_TABLE_ADDR
,
46 .tpm_final_log
= EFI_INVALID_TABLE_ADDR
,
47 #ifdef CONFIG_LOAD_UEFI_KEYS
48 .mokvar_table
= EFI_INVALID_TABLE_ADDR
,
50 #ifdef CONFIG_EFI_COCO_SECRET
51 .coco_secret
= EFI_INVALID_TABLE_ADDR
,
53 #ifdef CONFIG_UNACCEPTED_MEMORY
54 .unaccepted
= EFI_INVALID_TABLE_ADDR
,
59 unsigned long __ro_after_init efi_rng_seed
= EFI_INVALID_TABLE_ADDR
;
60 static unsigned long __initdata mem_reserve
= EFI_INVALID_TABLE_ADDR
;
61 static unsigned long __initdata rt_prop
= EFI_INVALID_TABLE_ADDR
;
62 static unsigned long __initdata initrd
= EFI_INVALID_TABLE_ADDR
;
64 extern unsigned long screen_info_table
;
66 struct mm_struct efi_mm
= {
67 .mm_mt
= MTREE_INIT_EXT(mm_mt
, MM_MT_FLAGS
, efi_mm
.mmap_lock
),
68 .mm_users
= ATOMIC_INIT(2),
69 .mm_count
= ATOMIC_INIT(1),
70 .write_protect_seq
= SEQCNT_ZERO(efi_mm
.write_protect_seq
),
71 MMAP_LOCK_INITIALIZER(efi_mm
)
72 .page_table_lock
= __SPIN_LOCK_UNLOCKED(efi_mm
.page_table_lock
),
73 .mmlist
= LIST_HEAD_INIT(efi_mm
.mmlist
),
74 .cpu_bitmap
= { [BITS_TO_LONGS(NR_CPUS
)] = 0},
77 struct workqueue_struct
*efi_rts_wq
;
79 static bool disable_runtime
= IS_ENABLED(CONFIG_EFI_DISABLE_RUNTIME
);
80 static int __init
setup_noefi(char *arg
)
82 disable_runtime
= true;
85 early_param("noefi", setup_noefi
);
87 bool efi_runtime_disabled(void)
89 return disable_runtime
;
92 bool __pure
__efi_soft_reserve_enabled(void)
94 return !efi_enabled(EFI_MEM_NO_SOFT_RESERVE
);
97 static int __init
parse_efi_cmdline(char *str
)
100 pr_warn("need at least one option\n");
104 if (parse_option_str(str
, "debug"))
105 set_bit(EFI_DBG
, &efi
.flags
);
107 if (parse_option_str(str
, "noruntime"))
108 disable_runtime
= true;
110 if (parse_option_str(str
, "runtime"))
111 disable_runtime
= false;
113 if (parse_option_str(str
, "nosoftreserve"))
114 set_bit(EFI_MEM_NO_SOFT_RESERVE
, &efi
.flags
);
118 early_param("efi", parse_efi_cmdline
);
120 struct kobject
*efi_kobj
;
123 * Let's not leave out systab information that snuck into
125 * Note, do not add more fields in systab sysfs file as it breaks sysfs
126 * one value per file rule!
128 static ssize_t
systab_show(struct kobject
*kobj
,
129 struct kobj_attribute
*attr
, char *buf
)
136 if (efi
.acpi20
!= EFI_INVALID_TABLE_ADDR
)
137 str
+= sprintf(str
, "ACPI20=0x%lx\n", efi
.acpi20
);
138 if (efi
.acpi
!= EFI_INVALID_TABLE_ADDR
)
139 str
+= sprintf(str
, "ACPI=0x%lx\n", efi
.acpi
);
141 * If both SMBIOS and SMBIOS3 entry points are implemented, the
142 * SMBIOS3 entry point shall be preferred, so we list it first to
143 * let applications stop parsing after the first match.
145 if (efi
.smbios3
!= EFI_INVALID_TABLE_ADDR
)
146 str
+= sprintf(str
, "SMBIOS3=0x%lx\n", efi
.smbios3
);
147 if (efi
.smbios
!= EFI_INVALID_TABLE_ADDR
)
148 str
+= sprintf(str
, "SMBIOS=0x%lx\n", efi
.smbios
);
150 if (IS_ENABLED(CONFIG_IA64
) || IS_ENABLED(CONFIG_X86
))
151 str
= efi_systab_show_arch(str
);
156 static struct kobj_attribute efi_attr_systab
= __ATTR_RO_MODE(systab
, 0400);
158 static ssize_t
fw_platform_size_show(struct kobject
*kobj
,
159 struct kobj_attribute
*attr
, char *buf
)
161 return sprintf(buf
, "%d\n", efi_enabled(EFI_64BIT
) ? 64 : 32);
164 extern __weak
struct kobj_attribute efi_attr_fw_vendor
;
165 extern __weak
struct kobj_attribute efi_attr_runtime
;
166 extern __weak
struct kobj_attribute efi_attr_config_table
;
167 static struct kobj_attribute efi_attr_fw_platform_size
=
168 __ATTR_RO(fw_platform_size
);
170 static struct attribute
*efi_subsys_attrs
[] = {
171 &efi_attr_systab
.attr
,
172 &efi_attr_fw_platform_size
.attr
,
173 &efi_attr_fw_vendor
.attr
,
174 &efi_attr_runtime
.attr
,
175 &efi_attr_config_table
.attr
,
179 umode_t __weak
efi_attr_is_visible(struct kobject
*kobj
, struct attribute
*attr
,
185 static const struct attribute_group efi_subsys_attr_group
= {
186 .attrs
= efi_subsys_attrs
,
187 .is_visible
= efi_attr_is_visible
,
190 static struct efivars generic_efivars
;
191 static struct efivar_operations generic_ops
;
193 static bool generic_ops_supported(void)
195 unsigned long name_size
;
200 name_size
= sizeof(name
);
202 status
= efi
.get_next_variable(&name_size
, &name
, &guid
);
203 if (status
== EFI_UNSUPPORTED
)
209 static int generic_ops_register(void)
211 if (!generic_ops_supported())
214 generic_ops
.get_variable
= efi
.get_variable
;
215 generic_ops
.get_next_variable
= efi
.get_next_variable
;
216 generic_ops
.query_variable_store
= efi_query_variable_store
;
217 generic_ops
.query_variable_info
= efi
.query_variable_info
;
219 if (efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE
)) {
220 generic_ops
.set_variable
= efi
.set_variable
;
221 generic_ops
.set_variable_nonblocking
= efi
.set_variable_nonblocking
;
223 return efivars_register(&generic_efivars
, &generic_ops
);
226 static void generic_ops_unregister(void)
228 if (!generic_ops
.get_variable
)
231 efivars_unregister(&generic_efivars
);
234 #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS
235 #define EFIVAR_SSDT_NAME_MAX 16UL
236 static char efivar_ssdt
[EFIVAR_SSDT_NAME_MAX
] __initdata
;
237 static int __init
efivar_ssdt_setup(char *str
)
239 int ret
= security_locked_down(LOCKDOWN_ACPI_TABLES
);
244 if (strlen(str
) < sizeof(efivar_ssdt
))
245 memcpy(efivar_ssdt
, str
, strlen(str
));
247 pr_warn("efivar_ssdt: name too long: %s\n", str
);
250 __setup("efivar_ssdt=", efivar_ssdt_setup
);
252 static __init
int efivar_ssdt_load(void)
254 unsigned long name_size
= 256;
255 efi_char16_t
*name
= NULL
;
262 name
= kzalloc(name_size
, GFP_KERNEL
);
267 char utf8_name
[EFIVAR_SSDT_NAME_MAX
];
268 unsigned long data_size
= 0;
272 status
= efi
.get_next_variable(&name_size
, name
, &guid
);
273 if (status
== EFI_NOT_FOUND
) {
275 } else if (status
== EFI_BUFFER_TOO_SMALL
) {
276 name
= krealloc(name
, name_size
, GFP_KERNEL
);
282 limit
= min(EFIVAR_SSDT_NAME_MAX
, name_size
);
283 ucs2_as_utf8(utf8_name
, name
, limit
- 1);
284 if (strncmp(utf8_name
, efivar_ssdt
, limit
) != 0)
287 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt
, &guid
);
289 status
= efi
.get_variable(name
, &guid
, NULL
, &data_size
, NULL
);
290 if (status
!= EFI_BUFFER_TOO_SMALL
|| !data_size
)
293 data
= kmalloc(data_size
, GFP_KERNEL
);
297 status
= efi
.get_variable(name
, &guid
, NULL
, &data_size
, data
);
298 if (status
== EFI_SUCCESS
) {
299 acpi_status ret
= acpi_load_table(data
, NULL
);
301 pr_err("failed to load table: %u\n", ret
);
305 pr_err("failed to get var data: 0x%lx\n", status
);
312 static inline int efivar_ssdt_load(void) { return 0; }
315 #ifdef CONFIG_DEBUG_FS
317 #define EFI_DEBUGFS_MAX_BLOBS 32
319 static struct debugfs_blob_wrapper debugfs_blob
[EFI_DEBUGFS_MAX_BLOBS
];
321 static void __init
efi_debugfs_init(void)
323 struct dentry
*efi_debugfs
;
324 efi_memory_desc_t
*md
;
326 int type_count
[EFI_BOOT_SERVICES_DATA
+ 1] = {};
329 efi_debugfs
= debugfs_create_dir("efi", NULL
);
330 if (IS_ERR_OR_NULL(efi_debugfs
))
333 for_each_efi_memory_desc(md
) {
335 case EFI_BOOT_SERVICES_CODE
:
336 snprintf(name
, sizeof(name
), "boot_services_code%d",
337 type_count
[md
->type
]++);
339 case EFI_BOOT_SERVICES_DATA
:
340 snprintf(name
, sizeof(name
), "boot_services_data%d",
341 type_count
[md
->type
]++);
347 if (i
>= EFI_DEBUGFS_MAX_BLOBS
) {
348 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
349 EFI_DEBUGFS_MAX_BLOBS
, EFI_DEBUGFS_MAX_BLOBS
);
353 debugfs_blob
[i
].size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
354 debugfs_blob
[i
].data
= memremap(md
->phys_addr
,
355 debugfs_blob
[i
].size
,
357 if (!debugfs_blob
[i
].data
)
360 debugfs_create_blob(name
, 0400, efi_debugfs
, &debugfs_blob
[i
]);
365 static inline void efi_debugfs_init(void) {}
369 * We register the efi subsystem with the firmware subsystem and the
370 * efivars subsystem with the efi subsystem, if the system was booted with
373 static int __init
efisubsys_init(void)
377 if (!efi_enabled(EFI_RUNTIME_SERVICES
))
378 efi
.runtime_supported_mask
= 0;
380 if (!efi_enabled(EFI_BOOT
))
383 if (efi
.runtime_supported_mask
) {
385 * Since we process only one efi_runtime_service() at a time, an
386 * ordered workqueue (which creates only one execution context)
387 * should suffice for all our needs.
389 efi_rts_wq
= alloc_ordered_workqueue("efi_rts_wq", 0);
391 pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
392 clear_bit(EFI_RUNTIME_SERVICES
, &efi
.flags
);
393 efi
.runtime_supported_mask
= 0;
398 if (efi_rt_services_supported(EFI_RT_SUPPORTED_TIME_SERVICES
))
399 platform_device_register_simple("rtc-efi", 0, NULL
, 0);
401 /* We register the efi directory at /sys/firmware/efi */
402 efi_kobj
= kobject_create_and_add("efi", firmware_kobj
);
404 pr_err("efi: Firmware registration failed.\n");
409 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE
|
410 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME
)) {
411 error
= generic_ops_register();
415 platform_device_register_simple("efivars", 0, NULL
, 0);
418 error
= sysfs_create_group(efi_kobj
, &efi_subsys_attr_group
);
420 pr_err("efi: Sysfs attribute export failed with error %d.\n",
425 /* and the standard mountpoint for efivarfs */
426 error
= sysfs_create_mount_point(efi_kobj
, "efivars");
428 pr_err("efivars: Subsystem registration failed.\n");
429 goto err_remove_group
;
432 if (efi_enabled(EFI_DBG
) && efi_enabled(EFI_PRESERVE_BS_REGIONS
))
435 #ifdef CONFIG_EFI_COCO_SECRET
436 if (efi
.coco_secret
!= EFI_INVALID_TABLE_ADDR
)
437 platform_device_register_simple("efi_secret", 0, NULL
, 0);
443 sysfs_remove_group(efi_kobj
, &efi_subsys_attr_group
);
445 if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE
|
446 EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME
))
447 generic_ops_unregister();
449 kobject_put(efi_kobj
);
453 destroy_workqueue(efi_rts_wq
);
458 subsys_initcall(efisubsys_init
);
460 void __init
efi_find_mirror(void)
462 efi_memory_desc_t
*md
;
463 u64 mirror_size
= 0, total_size
= 0;
465 if (!efi_enabled(EFI_MEMMAP
))
468 for_each_efi_memory_desc(md
) {
469 unsigned long long start
= md
->phys_addr
;
470 unsigned long long size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
473 if (md
->attribute
& EFI_MEMORY_MORE_RELIABLE
) {
474 memblock_mark_mirror(start
, size
);
479 pr_info("Memory: %lldM/%lldM mirrored memory\n",
480 mirror_size
>>20, total_size
>>20);
484 * Find the efi memory descriptor for a given physical address. Given a
485 * physical address, determine if it exists within an EFI Memory Map entry,
486 * and if so, populate the supplied memory descriptor with the appropriate
489 int __efi_mem_desc_lookup(u64 phys_addr
, efi_memory_desc_t
*out_md
)
491 efi_memory_desc_t
*md
;
493 if (!efi_enabled(EFI_MEMMAP
)) {
494 pr_err_once("EFI_MEMMAP is not enabled.\n");
499 pr_err_once("out_md is null.\n");
503 for_each_efi_memory_desc(md
) {
507 /* skip bogus entries (including empty ones) */
508 if ((md
->phys_addr
& (EFI_PAGE_SIZE
- 1)) ||
509 (md
->num_pages
<= 0) ||
510 (md
->num_pages
> (U64_MAX
- md
->phys_addr
) >> EFI_PAGE_SHIFT
))
513 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
514 end
= md
->phys_addr
+ size
;
515 if (phys_addr
>= md
->phys_addr
&& phys_addr
< end
) {
516 memcpy(out_md
, md
, sizeof(*out_md
));
523 extern int efi_mem_desc_lookup(u64 phys_addr
, efi_memory_desc_t
*out_md
)
524 __weak
__alias(__efi_mem_desc_lookup
);
527 * Calculate the highest address of an efi memory descriptor.
529 u64 __init
efi_mem_desc_end(efi_memory_desc_t
*md
)
531 u64 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
532 u64 end
= md
->phys_addr
+ size
;
536 void __init __weak
efi_arch_mem_reserve(phys_addr_t addr
, u64 size
) {}
539 * efi_mem_reserve - Reserve an EFI memory region
540 * @addr: Physical address to reserve
541 * @size: Size of reservation
543 * Mark a region as reserved from general kernel allocation and
544 * prevent it being released by efi_free_boot_services().
546 * This function should be called drivers once they've parsed EFI
547 * configuration tables to figure out where their data lives, e.g.
550 void __init
efi_mem_reserve(phys_addr_t addr
, u64 size
)
552 /* efi_mem_reserve() does not work under Xen */
553 if (WARN_ON_ONCE(efi_enabled(EFI_PARAVIRT
)))
556 if (!memblock_is_region_reserved(addr
, size
))
557 memblock_reserve(addr
, size
);
560 * Some architectures (x86) reserve all boot services ranges
561 * until efi_free_boot_services() because of buggy firmware
562 * implementations. This means the above memblock_reserve() is
563 * superfluous on x86 and instead what it needs to do is
564 * ensure the @start, @size is not freed.
566 efi_arch_mem_reserve(addr
, size
);
569 static const efi_config_table_type_t common_tables
[] __initconst
= {
570 {ACPI_20_TABLE_GUID
, &efi
.acpi20
, "ACPI 2.0" },
571 {ACPI_TABLE_GUID
, &efi
.acpi
, "ACPI" },
572 {SMBIOS_TABLE_GUID
, &efi
.smbios
, "SMBIOS" },
573 {SMBIOS3_TABLE_GUID
, &efi
.smbios3
, "SMBIOS 3.0" },
574 {EFI_SYSTEM_RESOURCE_TABLE_GUID
, &efi
.esrt
, "ESRT" },
575 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID
, &efi_mem_attr_table
, "MEMATTR" },
576 {LINUX_EFI_RANDOM_SEED_TABLE_GUID
, &efi_rng_seed
, "RNG" },
577 {LINUX_EFI_TPM_EVENT_LOG_GUID
, &efi
.tpm_log
, "TPMEventLog" },
578 {LINUX_EFI_TPM_FINAL_LOG_GUID
, &efi
.tpm_final_log
, "TPMFinalLog" },
579 {LINUX_EFI_MEMRESERVE_TABLE_GUID
, &mem_reserve
, "MEMRESERVE" },
580 {LINUX_EFI_INITRD_MEDIA_GUID
, &initrd
, "INITRD" },
581 {EFI_RT_PROPERTIES_TABLE_GUID
, &rt_prop
, "RTPROP" },
582 #ifdef CONFIG_EFI_RCI2_TABLE
583 {DELLEMC_EFI_RCI2_TABLE_GUID
, &rci2_table_phys
},
585 #ifdef CONFIG_LOAD_UEFI_KEYS
586 {LINUX_EFI_MOK_VARIABLE_TABLE_GUID
, &efi
.mokvar_table
, "MOKvar" },
588 #ifdef CONFIG_EFI_COCO_SECRET
589 {LINUX_EFI_COCO_SECRET_AREA_GUID
, &efi
.coco_secret
, "CocoSecret" },
591 #ifdef CONFIG_UNACCEPTED_MEMORY
592 {LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID
, &efi
.unaccepted
, "Unaccepted" },
594 #ifdef CONFIG_EFI_GENERIC_STUB
595 {LINUX_EFI_SCREEN_INFO_TABLE_GUID
, &screen_info_table
},
600 static __init
int match_config_table(const efi_guid_t
*guid
,
602 const efi_config_table_type_t
*table_types
)
606 for (i
= 0; efi_guidcmp(table_types
[i
].guid
, NULL_GUID
); i
++) {
607 if (efi_guidcmp(*guid
, table_types
[i
].guid
))
610 if (!efi_config_table_is_usable(guid
, table
)) {
611 if (table_types
[i
].name
[0])
612 pr_cont("(%s=0x%lx unusable) ",
613 table_types
[i
].name
, table
);
617 *(table_types
[i
].ptr
) = table
;
618 if (table_types
[i
].name
[0])
619 pr_cont("%s=0x%lx ", table_types
[i
].name
, table
);
626 int __init
efi_config_parse_tables(const efi_config_table_t
*config_tables
,
628 const efi_config_table_type_t
*arch_tables
)
630 const efi_config_table_64_t
*tbl64
= (void *)config_tables
;
631 const efi_config_table_32_t
*tbl32
= (void *)config_tables
;
632 const efi_guid_t
*guid
;
637 for (i
= 0; i
< count
; i
++) {
638 if (!IS_ENABLED(CONFIG_X86
)) {
639 guid
= &config_tables
[i
].guid
;
640 table
= (unsigned long)config_tables
[i
].table
;
641 } else if (efi_enabled(EFI_64BIT
)) {
642 guid
= &tbl64
[i
].guid
;
643 table
= tbl64
[i
].table
;
645 if (IS_ENABLED(CONFIG_X86_32
) &&
646 tbl64
[i
].table
> U32_MAX
) {
648 pr_err("Table located above 4GB, disabling EFI.\n");
652 guid
= &tbl32
[i
].guid
;
653 table
= tbl32
[i
].table
;
656 if (!match_config_table(guid
, table
, common_tables
) && arch_tables
)
657 match_config_table(guid
, table
, arch_tables
);
660 set_bit(EFI_CONFIG_TABLES
, &efi
.flags
);
662 if (efi_rng_seed
!= EFI_INVALID_TABLE_ADDR
) {
663 struct linux_efi_random_seed
*seed
;
666 seed
= early_memremap(efi_rng_seed
, sizeof(*seed
));
668 size
= min_t(u32
, seed
->size
, SZ_1K
); // sanity check
669 early_memunmap(seed
, sizeof(*seed
));
671 pr_err("Could not map UEFI random seed!\n");
674 seed
= early_memremap(efi_rng_seed
,
675 sizeof(*seed
) + size
);
677 add_bootloader_randomness(seed
->bits
, size
);
678 memzero_explicit(seed
->bits
, size
);
679 early_memunmap(seed
, sizeof(*seed
) + size
);
681 pr_err("Could not map UEFI random seed!\n");
686 if (!IS_ENABLED(CONFIG_X86_32
) && efi_enabled(EFI_MEMMAP
))
689 efi_tpm_eventlog_init();
691 if (mem_reserve
!= EFI_INVALID_TABLE_ADDR
) {
692 unsigned long prsv
= mem_reserve
;
695 struct linux_efi_memreserve
*rsv
;
699 * Just map a full page: that is what we will get
700 * anyway, and it permits us to map the entire entry
701 * before knowing its size.
703 p
= early_memremap(ALIGN_DOWN(prsv
, PAGE_SIZE
),
706 pr_err("Could not map UEFI memreserve entry!\n");
710 rsv
= (void *)(p
+ prsv
% PAGE_SIZE
);
712 /* reserve the entry itself */
713 memblock_reserve(prsv
,
714 struct_size(rsv
, entry
, rsv
->size
));
716 for (i
= 0; i
< atomic_read(&rsv
->count
); i
++) {
717 memblock_reserve(rsv
->entry
[i
].base
,
722 early_memunmap(p
, PAGE_SIZE
);
726 if (rt_prop
!= EFI_INVALID_TABLE_ADDR
) {
727 efi_rt_properties_table_t
*tbl
;
729 tbl
= early_memremap(rt_prop
, sizeof(*tbl
));
731 efi
.runtime_supported_mask
&= tbl
->runtime_services_supported
;
732 early_memunmap(tbl
, sizeof(*tbl
));
736 if (IS_ENABLED(CONFIG_BLK_DEV_INITRD
) &&
737 initrd
!= EFI_INVALID_TABLE_ADDR
&& phys_initrd_size
== 0) {
738 struct linux_efi_initrd
*tbl
;
740 tbl
= early_memremap(initrd
, sizeof(*tbl
));
742 phys_initrd_start
= tbl
->base
;
743 phys_initrd_size
= tbl
->size
;
744 early_memunmap(tbl
, sizeof(*tbl
));
748 if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY
) &&
749 efi
.unaccepted
!= EFI_INVALID_TABLE_ADDR
) {
750 struct efi_unaccepted_memory
*unaccepted
;
752 unaccepted
= early_memremap(efi
.unaccepted
, sizeof(*unaccepted
));
756 if (unaccepted
->version
== 1) {
757 size
= sizeof(*unaccepted
) + unaccepted
->size
;
758 memblock_reserve(efi
.unaccepted
, size
);
760 efi
.unaccepted
= EFI_INVALID_TABLE_ADDR
;
763 early_memunmap(unaccepted
, sizeof(*unaccepted
));
770 int __init
efi_systab_check_header(const efi_table_hdr_t
*systab_hdr
)
772 if (systab_hdr
->signature
!= EFI_SYSTEM_TABLE_SIGNATURE
) {
773 pr_err("System table signature incorrect!\n");
781 static const efi_char16_t
*__init
map_fw_vendor(unsigned long fw_vendor
,
784 const efi_char16_t
*ret
;
786 ret
= early_memremap_ro(fw_vendor
, size
);
788 pr_err("Could not map the firmware vendor!\n");
792 static void __init
unmap_fw_vendor(const void *fw_vendor
, size_t size
)
794 early_memunmap((void *)fw_vendor
, size
);
797 #define map_fw_vendor(p, s) __va(p)
798 #define unmap_fw_vendor(v, s)
801 void __init
efi_systab_report_header(const efi_table_hdr_t
*systab_hdr
,
802 unsigned long fw_vendor
)
804 char vendor
[100] = "unknown";
805 const efi_char16_t
*c16
;
809 c16
= map_fw_vendor(fw_vendor
, sizeof(vendor
) * sizeof(efi_char16_t
));
811 for (i
= 0; i
< sizeof(vendor
) - 1 && c16
[i
]; ++i
)
815 unmap_fw_vendor(c16
, sizeof(vendor
) * sizeof(efi_char16_t
));
818 rev
= (u16
)systab_hdr
->revision
;
819 pr_info("EFI v%u.%u", systab_hdr
->revision
>> 16, rev
/ 10);
825 pr_cont(" by %s\n", vendor
);
827 if (IS_ENABLED(CONFIG_X86_64
) &&
828 systab_hdr
->revision
> EFI_1_10_SYSTEM_TABLE_REVISION
&&
829 !strcmp(vendor
, "Apple")) {
830 pr_info("Apple Mac detected, using EFI v1.10 runtime services only\n");
831 efi
.runtime_version
= EFI_1_10_SYSTEM_TABLE_REVISION
;
835 static __initdata
char memory_type_name
[][13] = {
854 char * __init
efi_md_typeattr_format(char *buf
, size_t size
,
855 const efi_memory_desc_t
*md
)
862 if (md
->type
>= ARRAY_SIZE(memory_type_name
))
863 type_len
= snprintf(pos
, size
, "[type=%u", md
->type
);
865 type_len
= snprintf(pos
, size
, "[%-*s",
866 (int)(sizeof(memory_type_name
[0]) - 1),
867 memory_type_name
[md
->type
]);
868 if (type_len
>= size
)
874 attr
= md
->attribute
;
875 if (attr
& ~(EFI_MEMORY_UC
| EFI_MEMORY_WC
| EFI_MEMORY_WT
|
876 EFI_MEMORY_WB
| EFI_MEMORY_UCE
| EFI_MEMORY_RO
|
877 EFI_MEMORY_WP
| EFI_MEMORY_RP
| EFI_MEMORY_XP
|
878 EFI_MEMORY_NV
| EFI_MEMORY_SP
| EFI_MEMORY_CPU_CRYPTO
|
879 EFI_MEMORY_RUNTIME
| EFI_MEMORY_MORE_RELIABLE
))
880 snprintf(pos
, size
, "|attr=0x%016llx]",
881 (unsigned long long)attr
);
884 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
885 attr
& EFI_MEMORY_RUNTIME
? "RUN" : "",
886 attr
& EFI_MEMORY_MORE_RELIABLE
? "MR" : "",
887 attr
& EFI_MEMORY_CPU_CRYPTO
? "CC" : "",
888 attr
& EFI_MEMORY_SP
? "SP" : "",
889 attr
& EFI_MEMORY_NV
? "NV" : "",
890 attr
& EFI_MEMORY_XP
? "XP" : "",
891 attr
& EFI_MEMORY_RP
? "RP" : "",
892 attr
& EFI_MEMORY_WP
? "WP" : "",
893 attr
& EFI_MEMORY_RO
? "RO" : "",
894 attr
& EFI_MEMORY_UCE
? "UCE" : "",
895 attr
& EFI_MEMORY_WB
? "WB" : "",
896 attr
& EFI_MEMORY_WT
? "WT" : "",
897 attr
& EFI_MEMORY_WC
? "WC" : "",
898 attr
& EFI_MEMORY_UC
? "UC" : "");
903 * IA64 has a funky EFI memory map that doesn't work the same way as
904 * other architectures.
908 * efi_mem_attributes - lookup memmap attributes for physical address
909 * @phys_addr: the physical address to lookup
911 * Search in the EFI memory map for the region covering
912 * @phys_addr. Returns the EFI memory attributes if the region
913 * was found in the memory map, 0 otherwise.
915 u64
efi_mem_attributes(unsigned long phys_addr
)
917 efi_memory_desc_t
*md
;
919 if (!efi_enabled(EFI_MEMMAP
))
922 for_each_efi_memory_desc(md
) {
923 if ((md
->phys_addr
<= phys_addr
) &&
924 (phys_addr
< (md
->phys_addr
+
925 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
926 return md
->attribute
;
932 * efi_mem_type - lookup memmap type for physical address
933 * @phys_addr: the physical address to lookup
935 * Search in the EFI memory map for the region covering @phys_addr.
936 * Returns the EFI memory type if the region was found in the memory
937 * map, -EINVAL otherwise.
939 int efi_mem_type(unsigned long phys_addr
)
941 const efi_memory_desc_t
*md
;
943 if (!efi_enabled(EFI_MEMMAP
))
946 for_each_efi_memory_desc(md
) {
947 if ((md
->phys_addr
<= phys_addr
) &&
948 (phys_addr
< (md
->phys_addr
+
949 (md
->num_pages
<< EFI_PAGE_SHIFT
))))
956 int efi_status_to_err(efi_status_t status
)
964 case EFI_INVALID_PARAMETER
:
967 case EFI_OUT_OF_RESOURCES
:
970 case EFI_DEVICE_ERROR
:
973 case EFI_WRITE_PROTECTED
:
976 case EFI_SECURITY_VIOLATION
:
991 EXPORT_SYMBOL_GPL(efi_status_to_err
);
993 static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock
);
994 static struct linux_efi_memreserve
*efi_memreserve_root __ro_after_init
;
996 static int __init
efi_memreserve_map_root(void)
998 if (mem_reserve
== EFI_INVALID_TABLE_ADDR
)
1001 efi_memreserve_root
= memremap(mem_reserve
,
1002 sizeof(*efi_memreserve_root
),
1004 if (WARN_ON_ONCE(!efi_memreserve_root
))
1009 static int efi_mem_reserve_iomem(phys_addr_t addr
, u64 size
)
1011 struct resource
*res
, *parent
;
1014 res
= kzalloc(sizeof(struct resource
), GFP_ATOMIC
);
1018 res
->name
= "reserved";
1019 res
->flags
= IORESOURCE_MEM
;
1021 res
->end
= addr
+ size
- 1;
1023 /* we expect a conflict with a 'System RAM' region */
1024 parent
= request_resource_conflict(&iomem_resource
, res
);
1025 ret
= parent
? request_resource(parent
, res
) : 0;
1028 * Given that efi_mem_reserve_iomem() can be called at any
1029 * time, only call memblock_reserve() if the architecture
1030 * keeps the infrastructure around.
1032 if (IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK
) && !ret
)
1033 memblock_reserve(addr
, size
);
1038 int __ref
efi_mem_reserve_persistent(phys_addr_t addr
, u64 size
)
1040 struct linux_efi_memreserve
*rsv
;
1044 if (efi_memreserve_root
== (void *)ULONG_MAX
)
1047 if (!efi_memreserve_root
) {
1048 rc
= efi_memreserve_map_root();
1053 /* first try to find a slot in an existing linked list entry */
1054 for (prsv
= efi_memreserve_root
->next
; prsv
; ) {
1055 rsv
= memremap(prsv
, sizeof(*rsv
), MEMREMAP_WB
);
1058 index
= atomic_fetch_add_unless(&rsv
->count
, 1, rsv
->size
);
1059 if (index
< rsv
->size
) {
1060 rsv
->entry
[index
].base
= addr
;
1061 rsv
->entry
[index
].size
= size
;
1064 return efi_mem_reserve_iomem(addr
, size
);
1070 /* no slot found - allocate a new linked list entry */
1071 rsv
= (struct linux_efi_memreserve
*)__get_free_page(GFP_ATOMIC
);
1075 rc
= efi_mem_reserve_iomem(__pa(rsv
), SZ_4K
);
1077 free_page((unsigned long)rsv
);
1082 * The memremap() call above assumes that a linux_efi_memreserve entry
1083 * never crosses a page boundary, so let's ensure that this remains true
1084 * even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
1085 * using SZ_4K explicitly in the size calculation below.
1087 rsv
->size
= EFI_MEMRESERVE_COUNT(SZ_4K
);
1088 atomic_set(&rsv
->count
, 1);
1089 rsv
->entry
[0].base
= addr
;
1090 rsv
->entry
[0].size
= size
;
1092 spin_lock(&efi_mem_reserve_persistent_lock
);
1093 rsv
->next
= efi_memreserve_root
->next
;
1094 efi_memreserve_root
->next
= __pa(rsv
);
1095 spin_unlock(&efi_mem_reserve_persistent_lock
);
1097 return efi_mem_reserve_iomem(addr
, size
);
1100 static int __init
efi_memreserve_root_init(void)
1102 if (efi_memreserve_root
)
1104 if (efi_memreserve_map_root())
1105 efi_memreserve_root
= (void *)ULONG_MAX
;
1108 early_initcall(efi_memreserve_root_init
);
1111 static int update_efi_random_seed(struct notifier_block
*nb
,
1112 unsigned long code
, void *unused
)
1114 struct linux_efi_random_seed
*seed
;
1117 if (!kexec_in_progress
)
1120 seed
= memremap(efi_rng_seed
, sizeof(*seed
), MEMREMAP_WB
);
1122 size
= min(seed
->size
, EFI_RANDOM_SEED_SIZE
);
1125 pr_err("Could not map UEFI random seed!\n");
1128 seed
= memremap(efi_rng_seed
, sizeof(*seed
) + size
,
1132 get_random_bytes(seed
->bits
, seed
->size
);
1135 pr_err("Could not map UEFI random seed!\n");
1141 static struct notifier_block efi_random_seed_nb
= {
1142 .notifier_call
= update_efi_random_seed
,
1145 static int __init
register_update_efi_random_seed(void)
1147 if (efi_rng_seed
== EFI_INVALID_TABLE_ADDR
)
1149 return register_reboot_notifier(&efi_random_seed_nb
);
1151 late_initcall(register_update_efi_random_seed
);